Coaxial cables are widely used to carry high frequency electrical signals. Coaxial cables enjoy a relatively high bandwidth, low signal losses, are mechanically robust, and are relatively low cost. One particularly advantageous use of a coaxial cable is for connecting electronics at a cellular or wireless base station to an antenna mounted at the top of a nearby antenna tower. For example, the transmitter located in an equipment shelter may be connected to a transmit antenna supported by the antenna tower. Similarly, the receiver is also connected to its associated receiver antenna by a coaxial cable path.
A typical installation includes a relatively large diameter coaxial cable extending between the equipment shelter and the top of the antenna tower to thereby reduce signal losses. Some coaxial cables include a smooth outer conductor while other coaxial cables instead have a corrugated outer conductor. These coaxial cables also have an inner conductor and a dielectric between the outer conductor and the inner conductor. Some inner conductors are hollow, while other inner conductors are formed around an inner conductor dielectric core.
A typical connector for such a coaxial cable includes a connector housing to make an electrical connection to the outer conductor and a center contact to make electrical connection to the inner conductor of the coaxial cable. Such a connector may also include a back nut that is positioned onto the end of the outer conductor and adjacent the outer insulating jacket of the coaxial cable.
It is desirable for the connector to be securely affixed to the coaxial cable. Movement of the connector about the coaxial cable can lead to an undesired amount of intermodulation distortion, for example. Therefore, attempts have been made at designing connectors that securely attach to coaxial cables.
U.S. Pat. No. 7,011,546 to Vaccaro discloses a connector for a coaxial cable having a smooth outer conductor. The connector includes a connector housing, a back nut threadingly engaging a rearward end of the connector housing, a ferrule gripping and advancing an end of the coaxial cable into the connector housing as the back nut is tightened, and an insulator member positioned within a medial portion of the connector housing. The insulator member has a bore extending therethrough and includes a forward disk portion, a rearward disk portion, a ring portion connecting the forward and disk portions together, and a tubular outer conductor support portion extending rearwardly from the rearward disk portion for supporting an interior surface of the outer conductor of the coaxial cable.
A ferrule to receive the cable jacket therethrough is positioned in the back nut. The ferrule includes a supporting band portion and a plurality of circumferentially spaced apart gripping members carried by the support band portion. The gripping members include inner tabs that dig into the jacket, helping to reduce or eliminate axial movement of the connector with respect to the coaxial cable.
Despite these developments in connector technology, a need remains for connectors that may facilitate easy installation and that remain securely attached to the coaxial cable under a variety of operating conditions.